BUT-Info/S3/R3.04 (Qualité)

int method(int,int);
int method(int);
int method(float,float);

interface Iterator<E> {
    boolean hasNext();
    E next();
}

public <T> static void copy(Collection<? extends T> source, Collection<? super T> dest) {
    for (T t : source) {
         dest.add(t);
    }
}

int i = 0;  // cette déclaration indique explicitement que
            // la variable i est de type entier

/**
 * @author André Peninou
 */
public class Type {
  void m() {
    System.out.println ("Type");
    }
}
public class SousType extends Type {
  void m() {
    System.out.println ("SousType");
  }
  void autreM(){
    System.out.println ("Spécifique SousType");
  }
}
...
    Type a = new Type();
    a.m(); // "Type"

    a = new SousType();
    a.m(); // "SousType"
    // Statique : a est un Type (à la compil)
    // Dynamique : a est un SousType au runtime.

    // D'où :
    a = new SousType();
    a.autreM();
    // NOK car type statique == A => autreM() n'existe pas à la compilation
...

def calcule(a, b, c)
  return a*b+c
end

$a = calcule(6, 3, 2)
$b = calcule('6', 3, ', the number of the beast')

puts $a.to_s
puts $b.to_s

class Klass
   include Singleton
   # ...
end

a,b  = Klass.instance, Klass.instance

a == b
# => true

Klass.new
# => NoMethodError - new is private ...

public class Colvert extends Canard {

	protected Colvert() {
		this(new VolerAvecDesAiles(), new Cancan());
	}
...
c1 = new Colvert();

...
vol = new VolerAvecDesAiles();
cri = new Cancan();
c1 = new Colvert(vol,cri);
...

class Rectangle
{
	protected int m_width;
	protected int m_height;

	public void setWidth(int width){
		m_width = width;
	}

	public void setHeight(int height){
		m_height = height;
	}


	public int getWidth(){
		return m_width;
	}

	public int getHeight(){
		return m_height;
	}

	public int getArea(){
		return m_width * m_height;
	}
}

// Violation of Likov's Substitution Principle
class Square extends Rectangle
{
	public void setWidth(int width){
		m_width = width;
		m_height = width;
	}

	public void setHeight(int height){
		m_width = height;
		m_height = height;
	}

}

class LspTest
{
	private static Rectangle getNewRectangle()
	{
		// it can be an object returned by some factory ...
		return new Square();
	}

	public static void main (String args[])
	{
		Rectangle r = LspTest.getNewRectangle();

		r.setWidth(5);
		r.setHeight(10);
		// User knows that r is a rectangle.
		// It assumes that he's able to set the width and height as for the base class

		System.out.println(r.getArea());
		// Now she's surprised to see that the area is 100 instead of 50.
	}
}

class LspTest
{
	private static Square getNewSquare()
	{
		// it can be an object returned by some factory ...
		return new Rectangle();
	}

	public static void main (String args[])
	{
		Square s = LspTest.getNewSquare();

		s.setWidth(5);
		// User knows that r is a rectangle.
		// It assumes that he's able to set the width and height as for the base class

		System.out.println(s.getArea());
		// Now she's surprised to see that the area is 0 instead of 25.
	}
}